Just as Black or Native American would be a poor substitute for poor american.
Or Roma/Eskimo/Greenlander/Sami for Europe
Especially considering that the current prime minister and president of India are from so called backward communities.
India has come a long way in social development and using the "caste card" is quite out of taste.
The word "Caste" is of European origin and does not have a proper native equivalent.
The "caste system" itself is again a European concept imported into India to aid the colonial powers in their divide and rule.
Unlike the persecution of the Native Americans, Blacks, Jews or Aboriginal which were systematic state run pogroms often in democracies.
The fate of the "low caste" can be attributed to the fact that they were the most exploited, often to the point of death or slavery under colonial rule. While the so called "Upper caste" enjoyed second rung positions as peons, clerks and teachers. This experience is universal in the other colonies like Rwanda, Syria or Iraq where the words "Tribes" or "Clans" have come to substitute "Caste".
It must be noted that the newly independent India gave all Indians of both sexes the right to vote and went on further to provide "reservations" the equivalent of "affirmative action". This was long before the black American even got the right to vote. Less said about Europe the better, the "Roma" still get rounded up and "deported" even though as EU citizens they have the right to mobility.
"Caste" is a powerful tool for the unscrupulous politician inside India. The excuse of colonial apologists or more markedly the evangelists (if they are not the former) outside India.
Caste a European concept so prominent in the family names of Americans and Europeans, has today become synonymous with India thanks to the relentless propaganda of the colonialists/evangelists.